Normal anion gap acidosis

Normal anion gap acidosis
Classification and external resources
ICD-10	E87.2
ICD-9	276.2
DiseasesDB	29144

In renal physiology, normal anion gap acidosis, and less precisely non-anion gap acidosis, is an acidosis that is not accompanied by an abnormally increased anion gap.

The most common etiology of normal anion gap acidosis is diarrhea with a renal tubular acidosis being a distant second .

Differential diagnosis

The differential diagnosis of normal anion gap acidosis is relatively short (when compared to the differential diagnosis of acidosis):

• Hyperalimentation
• Acetazolamide and other carbonic anhydrase inhibitors
• Renal tubular acidosis^[1]
• Diarrhea
• Ureteroenteric fistula - an abnormal connection (fistula) between a ureter and the gastrointestinal tract
• Pancreaticoduodenal fistula - an abnormal connection between the pancreas and duodenum

It can be remembered with the mnemonic HARD-UP.^[2]

As opposed to high anion gap acidosis (which involves increased organic acid production), normal anion gap acidosis involves either increased production of chloride (hyperchloremic acidosis) or increased excretion of bicarbonate.

References

1. ^ "Metabolic Acidosis: Acid-Base Regulation and Disorders: Merck Manual Professional". http://www.merck.com/mmpe/sec12/ch157/ch157c.html#sec12-ch157-ch157c-1035. Retrieved 2008-12-04. 
2. ^ Mnemonic at medicalmnemonics.com 1797